The spinal column is a highly flexible structure comprising bones and connective tissue. Although the spine is capable of multiple degrees of motion, spinal injuries or anatomical irregularities may result in spinal pathologies that limit this range of motion.
Implant devices, such as vertebral spacers, intravertebral or intervertebral fusion devices and disc replacement devices, have been developed to assist with stabilization and fixation or functional support of the spine. Examples include pre-assembled rings, cages, boxes, dowels, and wedges of varying size and construction, such as meshes or plates, movable disc surfaces, gel or polymer spacers, elastomers and structures. However, all existing devices have certain drawbacks, such as difficulty of construction, insertion, bulkiness, inadequate surface coverage in area and/or height, multiple sizes (inventory) and others.
PCT/US2007/077495 describes an interbody spacer implant assembly for interbody fusion in a vertebral body and a method of insertion comprises a plurality of links and an elongated connector mechanism adapted to retain the plurality of links and allow the plurality of links to articulate with respect to one another.